Covers can be used to close holes leading from the street level down to a sewer or other utility connection. The covers allow cars and other vehicles to traverse the road without falling into the hole. Of course, before such holes can be entered their covers must be removed. Such covers are often made of cast iron and tend to be difficult to maneuver because of their size and weight. For example, manhole covers can weigh between 75-400 pounds.
Typically, manhole covers are removed using a long metal rod with a hook at the end. The hook is inserted into an aperture in the manhole cover. A person then physically lifts the cover off the casting that the cover rests on. This can be difficult due to the resting weight of the manhole cover. Further, these covers often stick to the casting thus making it more difficult to lift the cover. To free the covers, typically a person must pound on them with a maul or similar tool. Commonly one person will lift the cover while another person hammers on the cover. The combination of the two forces typically breaks the stuck cover loose. However, injuries to the back, toes, hands, and fingers of the workmen are not uncommon due to the difficulties in handling these heavy manhole covers. Further, there are other safety issues regarding the hook slipping while a person pulls on the cover. During removal, for instance, a person manually removing the cover risks losing balance and falling backwards into traffic if the hook slips while under tension.